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Diffstat (limited to 'arch/arm/kernel/traps.c')
-rw-r--r--arch/arm/kernel/traps.c49
1 files changed, 28 insertions, 21 deletions
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index abd2fc067736..0c8b10801d36 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -25,17 +25,20 @@
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/sched.h>
+#include <linux/irq.h>
#include <linux/atomic.h>
#include <asm/cacheflush.h>
#include <asm/exception.h>
#include <asm/unistd.h>
#include <asm/traps.h>
+#include <asm/ptrace.h>
#include <asm/unwind.h>
#include <asm/tls.h>
#include <asm/system_misc.h>
#include <asm/opcodes.h>
+
static const char *handler[]= {
"prefetch abort",
"data abort",
@@ -184,7 +187,7 @@ static void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk)
tsk = current;
if (regs) {
- fp = regs->ARM_fp;
+ fp = frame_pointer(regs);
mode = processor_mode(regs);
} else if (tsk != current) {
fp = thread_saved_fp(tsk);
@@ -458,10 +461,29 @@ die_sig:
arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6);
}
-asmlinkage void do_unexp_fiq (struct pt_regs *regs)
+/*
+ * Handle FIQ similarly to NMI on x86 systems.
+ *
+ * The runtime environment for NMIs is extremely restrictive
+ * (NMIs can pre-empt critical sections meaning almost all locking is
+ * forbidden) meaning this default FIQ handling must only be used in
+ * circumstances where non-maskability improves robustness, such as
+ * watchdog or debug logic.
+ *
+ * This handler is not appropriate for general purpose use in drivers
+ * platform code and can be overrideen using set_fiq_handler.
+ */
+asmlinkage void __exception_irq_entry handle_fiq_as_nmi(struct pt_regs *regs)
{
- printk("Hmm. Unexpected FIQ received, but trying to continue\n");
- printk("You may have a hardware problem...\n");
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ nmi_enter();
+
+ /* nop. FIQ handlers for special arch/arm features can be added here. */
+
+ nmi_exit();
+
+ set_irq_regs(old_regs);
}
/*
@@ -579,7 +601,6 @@ do_cache_op(unsigned long start, unsigned long end, int flags)
#define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE)
asmlinkage int arm_syscall(int no, struct pt_regs *regs)
{
- struct thread_info *thread = current_thread_info();
siginfo_t info;
if ((no >> 16) != (__ARM_NR_BASE>> 16))
@@ -630,21 +651,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs)
return regs->ARM_r0;
case NR(set_tls):
- thread->tp_value[0] = regs->ARM_r0;
- if (tls_emu)
- return 0;
- if (has_tls_reg) {
- asm ("mcr p15, 0, %0, c13, c0, 3"
- : : "r" (regs->ARM_r0));
- } else {
- /*
- * User space must never try to access this directly.
- * Expect your app to break eventually if you do so.
- * The user helper at 0xffff0fe0 must be used instead.
- * (see entry-armv.S for details)
- */
- *((unsigned int *)0xffff0ff0) = regs->ARM_r0;
- }
+ set_tls(regs->ARM_r0);
return 0;
#ifdef CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG
@@ -719,7 +726,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs)
dump_instr("", regs);
if (user_mode(regs)) {
__show_regs(regs);
- c_backtrace(regs->ARM_fp, processor_mode(regs));
+ c_backtrace(frame_pointer(regs), processor_mode(regs));
}
}
#endif